TITLE:
Occurrence of β-Lactamase Enzyme Genes and Integrons in Antibiotic Resistant Escherichia coli Isolates from Pregnant Women with Asymptomatic Bacteriuria in Nairobi, Kenya
AUTHORS:
Adelaide Ogutu Ayoyi, Gideon Kikuvi, Christine Bii, Samuel Kariuki
KEYWORDS:
Asymptomatic Bacteriuria, ESBLs Genes and Integrons
JOURNAL NAME:
Open Journal of Medical Microbiology,
Vol.15 No.4,
December
3,
2025
ABSTRACT: Asymptomatic bacteriuria (ASB) is the presence of bacteria in urine without apparent symptoms of urinary tract infections. Antibiotic treatment of asymptomatic bacteriuria in pregnant women is recommended to reduce the risks associated with urinary tract infection during pregnancy. However, antibiotic resistance affects the success of treatment leading to failure with adverse outcomes. The study was to investigate the presence of mobile antibiotic resistant factors in multidrug resistance E. coli isolates. Methods: This was a cross-sectional study involving 1020 women attending antenatal clinic in Nairobi County. The urine specimens were processed using standard methods for isolation and identification of bacteria in urine. The most common uropathogen, E. coli was tested for antimicrobial resistance, using polymerase chain reaction (PCR) to amplify beta-lactamase genes and integrase genes. Plasmid curing using ethidium bromide was performed on plasmid positive multidrug resistant isolates. Results: A total 219 of women tested positive for ASB, resulting to a prevalence of 21.5 % at 95% confidence level. A total of 85 positive samples were caused by Escherichia coli which was at 38.8%. E. coli isolates from this study had resistance to most antibiotics tested except for imipenem. The resistance ranged from 11.6% for gentamycin to 90.6% for ampicillin. PCR was used for amplification of mobile antibiotic resistant determinants and results indicated 21 isolates had integrons while 26 isolates yielded Beta-lactamase enzyme genes (OXA-1 (8)) and CTX-M (18). Conclusion: There was a significant ASB among pregnant women included in the study from the Nairobi county clinics. There is the presence of ESBLs genes and integrons in community-acquired E. coli infections.